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Journal of the Brazilian Chemical Society

Print version ISSN 0103-5053

Abstract

VALLE, M. Angélica del et al. Nucleation and growth mechanisms of poly(furan): effect of electrolyte and monomer concentration in acetonitrile. J. Braz. Chem. Soc. [online]. 2004, vol.15, n.2, pp. 272-276. ISSN 0103-5053.  http://dx.doi.org/10.1590/S0103-50532004000200018.

The effects of monomer and tetrabuthylammonium hexafluorophosphate concentration on the nucleation and growth processes of polyfuran on Pt disc electrode in CH3CN have been studied through the step potential method. The j/t transients were fitted by means of a mathematical equation that considers different contributions. At the first stage of the transient (0 < t < 20 s), there are three contributions corresponding to IN2D and IN3D mechanisms controlled by charge transfer, and PN3D mechanism under diffusion control. The analyzed parameters have a distinct effect on the contributions involved in the nucleation and growth processes; however the IN3D mechanism was always the most important contribution. Nevertheless, depending on the monomer concentration, the contribution under diffusion control can be more or less important, which confirms the formation of an "oligomeric region" in the interface, during the polymerization process.

Keywords : furan [poly(furan)]; furan [nucleation]; growth [nucleation and growth mechanisms].

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